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The PrincipalNameRegex (basic:PrincipalNameRegex prior to V3.2) type describes a PolicyRule which returns true if the canonicalized principal used to identify the user matches matches the supplied Java regular expression. See AuthenticationConfiguration for a discussion of principal name canonicalization during authentication.
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The PrincipalNameRegex type is defined by defined in the urn:mace:shibboleth:2.0:afp namespace, the schema for which can be located at http://shibboleth.net/schema/idp/shibboleth-afp.xsd
Prior to V3.2.0 the deprecated basic:PrincipalNameRegex type is defined by defined in the urn:mace:shibboleth:2.0:afp:mf:basic namespace, the schema for which can be located at http://shibboleth.net/schema/idp/shibboleth-afp-mf-basic.xsd
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Only one attributes may be specified
regex: a required attribute which specifies the java regular expression to match against
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